Identifying Accessory Mineral Saturation during Differentiation in Granitoid Magmas: an Integrated Approach

Hoskin, Paul W. O.; Kinny, Peter D.; Wyborn, D.; Chappell, B. W.

doi:10.1093/petrology/41.9.1365

Cited by 351 publications

(127 citation statements)

References 64 publications

Supporting

Mentioning

106

Contrasting

Unclassified

Order By: Relevance

“…Thus, in experiments using ilmenites from garnet pyroxenite it was determined that the values of D (ilmenite / melt) successively increase from La (∼0.00003) to Yb (0.2) and then slightly decrease towards Lu (0.1) [58]. A similar trend in the values of these D from light to HREE was ascertained in the course of another experiment, but in this case the obtained values were slightly different: from 0.0072 -for La to 0.029 -for Lu [103]. Based on the results of the determination of …”

Section: Ilmenitessupporting

confidence: 57%

“…Therefore, in order to maintain a real balance of charges during the isomorphous entrance of REE into the zircon structure, obviously, there should be involved some additional ions as charge compensators [97,103]. In this context a theory emerged, according to which the function of compensating the charge could be carried out by such ions as Mo 4+ , Li + and others, and the heterovalent REE isomorphism in zircons could have the following form [104] During the reconstruction of the crystallization conditions of natural zircons a considerable attention is usually paid at positive Ce anomalies and negative Eu anomalies observed in many of their REE patterns.…”

Section: Zirconsmentioning

confidence: 99%

See 1 more Smart Citation

Consistent patterns of rare earth element distribution in accessory minerals from rocks of mafic-ultramafic complexes

Lesnov

2013

Open Geosciences

View full text Add to dashboard Cite

This paper summarizes analytical data accumulated in the world literature and other materials about the regularities of the REE distribution in minerals contained in ultramafic and mafic rocks as accessory phases. These minerals are tentatively divided into two groups. The first includes garnets, zircons, apatites and perovskites, which can accumulate increased amounts of REE in their structure. The second consists of minerals whose structure can accumulate only limited contents of these trace elements. These are chrome-spinels, ilmenites, and micas. These minerals, in respect of REE geochemistry, are studied to a varying degree because of the different levels of accumulations of these elements, different degrees of occurrence in rocks, tiny sizes of their grains and other reasons. The analytical database formed on their basis includes about 600 original analyses. The overwhelming majority of presently available data on REE geochemistry in accessory minerals from ultramafic and mafic rocks have been published only in the recent 15 years. The studies became possible due to the development and introduction of new highly sensible microprobe analyses allowing detection of REE and many other trace elements in minerals grains directly in thin sections. The greatest numbers of these analyses were performed for garnets and zircons, fewer for apatites, and the fewest for chrome-spinels, ilmenites, micas, and perovskites. In general, the regularities of REE distribution in these minerals from ultramafic and mafic rocks are less studied compared to the rock-forming minerals from ultramafic and mafic rocks. Among the analytical methods, which were used to study the REE composition of accessory minerals, the most efficient was the mass-spectrometry with inductively coupled plasma (ICP-MS).Keywords: REE distribution • ultramafic and mafic rocks • accessory minerals © Versita Sp. z o.o.

show abstract

Section: Ilmenitessupporting

confidence: 57%

Section: Zirconsmentioning

confidence: 99%

Consistent patterns of rare earth element distribution in accessory minerals from rocks of mafic-ultramafic complexes

Lesnov

2013

Open Geosciences

View full text Add to dashboard Cite

show abstract

“…Using Lu-and P-doped synthetic zircons, Trail et al (2016) carried out "in" diffusion and heating experiments, and their "in" diffusion experiments showed no discernable difference in Li diffusivity when compared to Cherniak and Watson's results. These Hoskin et al (2000) experimental studies reveal that another substitution mechanism for Li in zircon that does not involve coupling with REE and Y creates a fast diffusion mode. On the other hand, the current diffusion experiments do not negate a charge coupling mechanism between and Li and REE+Y.…”

Section: Experimental Perspectives On LI Diffusion In Zirconmentioning

confidence: 80%

Multi-mode Li diffusion in natural zircons: Evidence for diffusion in the presence of step-function concentration boundaries

Tang

Rudnick

McDonough

et al. 2017

Earth and Planetary Science Letters

View full text Add to dashboard Cite

Available online xxxx Editor: A. Yin Keywords:Li diffusion zircon charge coupling geospeedometer ToF-SIMS NanoSIMS Micron-to submicron-scale observations of Li distribution and Li isotope composition profiles can be used to infer the mechanisms of Li diffusion in natural zircon. Extreme fractionation (20-30❤) within each single crystal studied here confirms that Li diffusion commonly occurs in zircon. Sharp Li concentration gradients frequently seen in zircons suggest that the effective diffusivity of Li is significantly slower than experimentally determined (Cherniak and Watson, 2010;Trail et al., 2016), otherwise the crystallization/metamorphic heating of these zircons would have to be unrealistically fast (years to tens of years). Charge coupling with REE and Y has been suggested as a mechanism that may considerably reduce Li diffusivity in zircon (Ushikubo et al., 2008;Bouvier et al., 2012). We show that Li diffused in the direction of decreasing Li/Y ratio and increasing Li concentration (uphill diffusion) in one of the zircons, demonstrating charge coupling with REE and Y. Quantitative modeling reveals that Li may diffuse in at least two modes in natural zircons: one being slow and possibly coupled with REE+Y, and the other one being fast and not coupled with REE+Y. The partitioning of Li between these two modes during its diffusion may depend on the pre-diffusion substitution mechanism of REE and Y in the zircon lattice. Based on our results, sharp Li concentration gradients are not indicative of limited diffusion, and can be preserved at temperatures >700 • C on geologic timescales. Finally, large δ 7 Li variations observed in the Hadean Jack Hills zircons may record kinetic fractionation, rather than a record of ancient intense weathering in the granite source materials.

show abstract

“…In felsic igneous rocks, whilst the major elements are hosted largely in the main rock-forming minerals, the trace element budget is commonly controlled by accessory minerals (Wark & Miller, 1993;Bea, 1996;Hoskin et al, 2000;Claiborne et al, 2010). These include apatite and zircon, which are both ubiquitous phenocrysts in the Viséan NDB bentonites.…”

Section: Resultsmentioning

confidence: 99%

Geochemistry and origin of Carboniferous (Mississippian; Viséan) bentonites in the Namur-Dinant Basin, Belgium: evidence for a Variscan volcanic source

Pointon¹,

Chew²,

Delcambre³

et al. 2018

Geol. Belg.

View full text Add to dashboard Cite

ABSTRACT. Several thin clay-rich horizons occur interbedded with Mississippian (Viséan) limestones in the Namur-Dinant Basin, southern Belgium. These have been interpreted as diagenetically altered volcanic ash layers (bentonites). Whole-rock geochemical analysis of several bentonites was undertaken to provide insight into their original magmatic composition. Ratios of several trace elements that are considered to be immobile during diagenetic alteration and indicators of petrogenetic processes suggest that most of the bentonites were originally trachyandesitic to trachytic ashes. Furthermore, the coarse grain size of euhedral zircon phenocrysts (up to 400 µm in length) suggests a proximal volcanic source. Zircon U-Pb isotopic ages and wholerock geochemical data from these bentonites were compared with literature data from volcanic and intrusive rocks in adjacent areas, and suggest that the bentonites were sourced from volcanoes within the Variscan orogenic belt.KEYWORDS: altered volcanic ash, cinerite, whole-rock geochemistry, trace element geochemistry, X-ray diffraction analysis.http://dx

show abstract

Identifying Accessory Mineral Saturation during Differentiation in Granitoid Magmas: an Integrated Approach

Cited by 351 publications

References 64 publications

Consistent patterns of rare earth element distribution in accessory minerals from rocks of mafic-ultramafic complexes

Consistent patterns of rare earth element distribution in accessory minerals from rocks of mafic-ultramafic complexes

Multi-mode Li diffusion in natural zircons: Evidence for diffusion in the presence of step-function concentration boundaries

Geochemistry and origin of Carboniferous (Mississippian; Viséan) bentonites in the Namur-Dinant Basin, Belgium: evidence for a Variscan volcanic source

Contact Info

Product

Resources

About